Apple provides software updates for hardware 5 to 7 years after the date of discontinuation.
Meaning those models will only update to Big Sur. But will get all the updates for Bug sur.
They will no go past Big Sur, so what you are calling support is actually versions newer then Big Sur and/or security updates.
IF a major security issue comes along Apple may still provide an update for older versions of Mac OS but Big Sur would be likely the oldest supported version.
As long as the "Patch" you are referring to is the one that I think you are (can't remember the name) all it does is change a listing in a config file so you should be OK there BUT keep in mind, that hardware was never tested for whatever version of MacOS you put on it past Big Sur and performance may not be what you think it should be.
Also, Apple will not provide phone support for those models past Big Sur, so you become your own help desk.
it could run fine, no problems.
it could run slower but usable
it could run unbearably slow
it could fry your battery in a puff of light grey smoke.
No body knows until you try it.. so report back and let us know.